124 DISSEMINATION OF SEEDS. 



far and wide. When we think how small, how incon- 

 spicuous these seeds and the spores which in Cryptogams 

 take the place of seeds are. we do not wonder that we 

 have either no ocular proof or but little such proof of this 

 method of their transportation. 



Many seeds are specially adapted for transportation by 

 the wind from one place to another. This is peculiarly 

 true of the seeds of the Composite many of which are 

 furnished with a feathery appendage evidently designed 

 to assist in the carrying of the seeds to a distance. As 

 illustrations may be mentioned the Taraxacum, Leonto- 

 don, Cirsium, Erechthites, Senecio, Gnaphalium, and 

 Solidago, popularly known as the spring and fall dan- 

 delions, thistle, fireweed, groundsel, everlasting, and 

 goldenrod. These plants are members of the largest 

 family of the vegetable kingdom and-, if we consider the 

 structure of their flowers, we shall be at no loss to decide 

 why the family is so numerous and so widely scattered. 



The Taraxacum dens-leonis, dandelion, may serve as 

 the flower to be specially studied. With its brilliantly 

 colored head resembling a flower, we are all familiar. 

 The apparently single blossom is really a cluster of many 

 sessile florets crowded together upon a common receptacle 

 and surrounded by an involucre. Each floret is an illus- 

 tration of the changes in shape which the organs of plants 

 undergo in their adaptation to certain ends. The limb of 

 its calyx is reduced to a tuft of hairs ; the five little 

 notches at the end of its strap-shaped corolla show how 

 its five petals have been united into a gamopetalous co- 

 rolla and altered from the tubular form by being split 

 down the side and laid open ; its stamens are united by 

 their anthers around the forked style of the pistil. The 

 tube of the calyx is incorporated with the surface of the 

 ovary while its limb separates into a circle of hairs called 



